Station and system for press forming glass sheets

ABSTRACT

A press station ( 12 ) and system ( 10 ) for forming glass sheets that are initially formed with an upwardly concave curved shape with end portions ( 86 ) and an intermediate portion ( 88 ) having straight line elements that are subsequently formed with curved shapes to provide curvature along transverse directions. The forming is performed by initially providing curvature to the straight line elements of the glass sheet end portions ( 86 ) while the intermediate portion ( 88 ) still has the straight line elements. The glass sheet intermediate portion is subsequently formed to provide curvature to its straight line elements so the entire glass sheet has curvature in transverse directions.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a division of U.S. application Ser. No. 12/796,962filed Jun. 9, 2010, which issued as U.S. Pat. No. 9,296,637 on Mar. 29,2016, the entire disclosure of which is hereby incorporated byreference.

TECHNICAL FIELD

This invention relates to a press station for forming glass sheets, andto a press forming system that includes the press station for formingglass sheets.

BACKGROUND

Glass sheets can be press formed, which also is sometimes referred to asbeing press bent, after being heated sufficiently to permit suchforming. This forming can be with curvature that has straight lineelements as have cylindrical or conical shapes. Actually, in the pressforming industry, conical glass sheets having the straight line elementsare referred to as cylindrical curvature just like those with actualcylindrical shapes having the straight line elements. As disclosed inU.S. Pat. No. 6,543,255 Bennett et al. and U.S. Pat. No. 6,578,383Bennett et al., the entire disclosures of which are hereby incorporatedby reference, glass sheets heated within a heating chamber to asufficiently high temperature for forming can be roll formed by inclinedrolls and then conveyed to a press station for press forming to a finalshape. The press forming can be so as to maintain the straight lineelements or to provide curvature to the straight line elements so thatthe glass sheet is formed in transverse directions, which in the glassindustry is referred to as being formed with “cross bend” or “crosscurvature.”

SUMMARY

One object of the present invention is to provide an improved glasssheet press station.

In carrying out the above object, the glass sheet press station includesa conveyor for conveying along a direction of conveyance a heated andinitially formed glass sheet having an upwardly concave shape includingupper end portions spaced laterally from each other with respect to thedirection of conveyance and a lower intermediate portion that extendstransversely with respect to the direction of conveyance between the endportions, with the upper end portions and the lower intermediate portionhaving straight line elements, and with the glass sheet curvedtransversely to the straight line elements. The press station includes alower ring over which the glass sheet is conveyed. The lower ringincludes a support frame and also has a pair of rigid upwardly concaveend portions on the support frame spaced laterally from each otherrelative to the direction of conveyance with rigid upwardly concavecurved shapes along the direction of conveyance, the lower ring also hasa pair of rigid upwardly concave intermediate portions on the supportframe spaced from each other along the direction of conveyance withrigid upwardly concave curved shapes extending transversely to thedirection of conveyance between the end portions of the lower ring. Theend portions of the lower ring each includes a connection that permitsvertical movement thereof relative to the support frame, and theintermediate portions of the lower ring each includes a connection thatprevents movement thereof relative to the support frame so the endportions and the intermediate portions are movable vertically togetherwith each other and independently of each other. An upper mold of thepress station is located above the lower ring and has a downwardlyfacing surface with downwardly convex curvature both along andtransverse to the direction of conveyance in complementary relationshipto the curvature of the end portions and intermediate portions of thelower ring. An actuator of the press station is configured to: initiallymove the end portions and the intermediate portions of the lower ringupwardly together with each other by upward movement of the supportframe to lift the initially formed glass sheet upwardly off of theconveyor; then move the end portions of the lower ring upwardly relativeto the support frame and the intermediate portions of the lower ring tomove the end portions of the glass sheet upwardly into contact with thedownwardly facing surface of the upper mold to provide curvature to thestraight line elements of the end portions of the glass sheet while theintermediate portion of the glass sheet has not yet been formed by theupper mold; and thereafter move the support frame upwardly to move theintermediate portions of the lower ring upwardly relative to its endportions to contact and form the intermediate portion of the glass sheetagainst the downwardly facing surface of the upper mold to providecurvature to the straight line elements of the intermediate portion ofthe glass sheet so the entire glass sheet has curvature in transversedirections.

The lower ring of the press station is disclosed as including a pair ofpivotal connections that respectively pivotally mount the end portionsof the lower ring on the support frame for the vertical movement withrespect thereto and with respect to the intermediate portions of thelower ring. The pair of pivotal connections as shown each includespivotal arms having first ends that are pivotally mounted on the supportframe and second ends that respectively mount the associated end portionof the lower ring.

The actuator of the press station is disclosed as including cylindersfor applying upward force to the end portions of the lower ring so as tomove upwardly relative to the support frame and the intermediateportions of the lower ring to provide the movement of the end portionsof the glass sheet upwardly into contact with the downwardly facingsurface of the upper mold to provide forming thereof along the directionof conveyance while the intermediate portion of the glass sheet has notyet been formed by the upper mold. Furthermore, the actuator may operatethe cylinders to reduce the upward force applied to the end portions ofthe lower ring as the intermediate portions of the lower ring are movedupwardly relative to the end portions of the lower ring to facilitatemovement of the glass sheet end portions relative to the downwardlyfacing surface of the upper mold as the intermediate portions of thelower ring move the intermediate portion of the glass sheet into contactwith the downwardly facing surface of the upper mold to provide theforming thereof along the direction of conveyance. In addition, thelower ring is disclosed as including adjustors for adjusting thepositions of its rigid upwardly concave end portions and rigid upwardlyconcave intermediate portions relative to the support frame and eachother.

Another object of the present invention is to provide an improved glasssheet press forming system.

In carrying out the immediately preceding object, the glass sheet pressforming system includes a conveyor for conveying glass sheets along adirection of conveyance and a furnace having a heating chamber throughwhich the conveyor conveys glass sheets from an entrance end of thefurnace toward an exit end thereof for heating in preparation forforming. Adjacent its exit end the furnace includes inclined rolls ofprogressively increasing inclination along the direction of conveyanceso as to initially form each glass sheet with an upwardly concave curvedshape extending transversely with respect to the direction of conveyancewith upper end portions and a lower intermediate portion extendingbetween the end portions, with the upper end portions and the lowerintermediate portion having straight line elements, and with the glasssheet curved transversely to the straight line elements. The systemincludes a press station to which the conveyor conveys the initialformed glass sheet at a location downstream from the exit end of thefurnace. The press station includes a lower ring over which the glasssheet is conveyed. The lower ring includes a support frame and alsoincluding a pair of rigid upwardly concave end portions on the supportframe spaced laterally from each other relative to the direction ofconveyance with rigid upwardly concave curved shapes along the directionof conveyance, and the lower ring further includes a pair of rigidupwardly concave intermediate portions on the support frame spaced fromeach other along the direction of conveyance with rigid upwardly concavecurved shapes extending transversely to the direction of conveyancebetween the end portions of the lower ring. The end portions of thelower ring each includes a connection that permits vertical movementthereof relative to the support frame, and the intermediate portions ofthe lower ring each includes a connection that prevents movement thereofrelative to the support frame so the end portions and the intermediateportions are movable vertically together with each other andindependently of each other. The press station also includes an uppermold located above the lower ring and having a downwardly facing surfacewith convex curvature both along and transverse to the direction ofconveyance in complementary relationship to the curvature of the endportions and intermediate portions of the lower ring. An actuator of thepress station is configured to: initially move the end portions and theintermediate portions of the lower ring upwardly together with eachother by upward movement of the support frame to lift the initiallyformed glass sheet upwardly off of the conveyor; then move the endportions of the lower ring upwardly relative to the support frame andthe intermediate portions of the lower ring to move the end portions ofthe glass sheet upwardly into contact with the downwardly facing surfaceof the upper mold to provide curvature to the straight line elements ofthe end portions of the glass sheet while the intermediate portion ofthe glass sheet is still below and has not yet been formed by the uppermold; and thereafter move the support frame upwardly to move theintermediate portions of the lower ring upwardly relative to its endportions to contact the intermediate portion of the glass sheet with thedownwardly facing surface of the upper mold to provide curvature to thestraight line elements of the intermediate portion of the glass sheet sothe entire glass sheet has curvature in transverse directions.

The objects, features and advantages of the present invention arereadily apparent from the following detailed description of thepreferred embodiment when taken in connection with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic side elevation view of a glass sheet press formingsystem that includes a glass sheet press station whose operationperforms forming of glass sheets in transverse directions.

FIG. 2 is a schematic cross sectional view through the system takenalong the direction of line 2-2 in FIG. 1 at an exit end of a furnace ofthe system and illustrates horizontal and inclined rolls on which heatedglass sheets are conveyed for initial roll forming prior to exiting thefurnace in preparation for press forming.

FIG. 3 is a schematic cross sectional view taken through the systemalong line 3-3 in FIG. 1 at its press station to illustrate theconstruction of a lower ring and an upper press mold that are movablebetween the solid and phantom line indicated positions to press bend theinitially roll formed glass sheet.

FIG. 4 is a perspective view illustrating wheel conveyor assemblies ofthe conveyor that convey the initially formed glass sheet to above thelower ring of the press station for the press forming.

FIG. 5 is a side elevational view of the upper mold taken in the samedirection as FIG. 1 to illustrate its downwardly facing surface againstwhich the final forming takes place.

FIG. 6 is a perspective view of the upper mold turned upside down toillustrate the curvature of the downwardly facing mold surface intransverse directions both along and transverse to the direction ofconveyance.

FIG. 7 is a perspective view of the lower ring.

FIG. 8 is a top plan view of the lower ring.

FIG. 9 is an elevational view of the lower ring taken along thedirection of line 9-9 in FIG. 8, which is in the direction ofconveyance, but with portions of the lower ring removed to illustrateits left and right end portions as being at the same elevation as leftand right ends of intermediate portions of the lower ring which is thepositioning involved during initial and final processing at the pressstation.

FIG. 10 is a view similar to FIG. 9 but shows the lower ring with itsright and left end portions raised with respect to the right and leftends of the intermediate portions of the lower ring which is positioninginvolved during an intermediate portion of the press forming operation.

FIG. 11 is a schematic view at the press station taken along thedirection of conveyance and showing the manner in which the wheelconveyor assemblies convey the glass sheet into the press station abovethe lower ring and below the upper mold.

FIG. 12 is a schematic view similar to FIG. 11 but taken at a laterstage after the lower ring has moved upwardly to lift the initiallyformed glass sheet upwardly off the conveyor into proximity with thedownwardly facing surface of the upper mold.

FIG. 13 is a schematic view similar to FIG. 12 but at a still laterstage of the press bending cycle after end portions of the lower ringhave lifted end portions of the initially formed glass sheet upwardlyinto contact with the downwardly facing surface of the upper mold.

FIG. 14 is a schematic view similar to FIG. 13 but at a later stageafter the intermediate portions of the lower ring have been movedupwardly to contact the intermediate portion of the glass sheet with thedownwardly facing surface of the upper mold to complete the pressforming of the glass sheet in transverse directions both along andtransverse to the direction of conveyance.

DETAILED DESCRIPTION

As required, detailed embodiments of the present invention are disclosedherein; however, it is to be understood that the disclosed embodimentsare merely exemplary of the invention that may be embodied in variousand alternative forms. The figures are not necessarily to scale; somefeatures may be exaggerated or minimized to show details of particularcomponents. Therefore, specific structural and functional detailsdisclosed herein are not to be interpreted as limiting, but merely as arepresentative basis for teaching one skilled in the art to variouslyemploy the present invention.

With reference to FIG. 1 of the drawings, a system for press formingglass sheets is generally indicated by 10 and includes a press formingstation 12. The constructions of the press station and the system willbe described in an integrated manner to facilitate an understanding ofdifferent aspects of the invention.

With continuing reference to FIG. 1, the system 10 includes a furnace 14having a roll forming station 16 just upstream along a direction ofconveyance C from the press bending station 12. Downstream from thepress forming station 12 along the direction of conveyance C, the system10 is illustrated as including a final processing station 18 at whichthe formed glass sheet can be slowly cooled for annealing or morerapidly cooled by quenching to provide heat strengthening or tempering.

As illustrated by continuing reference to FIG. 1, the furnace 14 hasentry and exit ends 20 and 22 and includes a heating chamber 24 (FIG. 2)having a conveyor 26 for conveying glass sheets along the direction ofconveyance through the furnace from the entry end to the exit end. Theconveyor 26 on which the glass sheets are heated can be either aconventional gas hearth or a roll conveyor on which the glass sheets areconveyed during heating from ambient temperature to a sufficiently hightemperature to permit forming, i.e., also referred to as bending in theglass sheet industry.

The furnace exit end 22 includes the roll forming station 16 which isillustrated in FIG. 2 as having horizontally extending conveyor rolls 28that are rotatively driven and spaced horizontally within the heatingchamber along the direction of conveyance extending laterally withrespect thereto to support and convey the heated glass sheets. The rollforming station 16 also includes a pair of sets 30 of bending rolls 32,with the bending roll sets 30 spaced laterally with respect to eachother within the heating chamber 24 along the direction of conveyance.Each set of bending rolls 30 is supported and rotatively driven by adrive mechanism 33 with the bending rolls at progressively increasinginclinations along the direction of conveyance as illustrated byreference numerals 32 a, 32 b, 32 c and 32 d in FIG. 2. The conveyanceof each heated glass sheet G along the direction of conveyance incooperation with the bending rolls 32 provides initial forming of theglass sheet G along a direction transverse to the direction ofconveyance as illustrated in FIG. 2. This forming provides the glasssheet with straight line element that may be parallel to each other in acylindrical shape or angled with respect to each other in a conicalshape. As each location of the glass sheet along the direction ofconveyance is bent from its flat shape, this bending also further bendsthe preceding location such that the net effect is a slightly conicalshape.

With combined reference to FIGS. 1 and 3, the press station 12 aspreviously mentioned is located externally of the furnace 14 downstreamfrom its exit end 22 to receive the initially formed glass sheets fromthe roll forming station 16. More specifically, the press station 12includes a lower wheel bed 34 of the conveyor for receiving an initiallyformed glass sheet to be further press formed by press forming apparatuscollectively indicated by 36. The lower wheel bed 34 includes a lowerbase structure 38 and a plurality of conveyor wheel assemblies 40. Eachwheel assembly 40 as is hereinafter more fully described includes ahousing having an upper end including a wheel 44 and having a lower endincluding a detachable connection 46 for detachably connecting the wheelassembly to the support 38. A drive mechanism provides rotationaldriving of the wheel 44 of each wheel assembly 40 upon connectionthereof to the support 38. For a more detailed description of theconveyor and the drive mechanism, refer to U.S. Pat. No. 6,543,255 whichhas previously been incorporated by reference. Also, it should be notedthat the conveyor instead of having only wheel conveyor assemblies canalso have elongated roller conveyor assemblies both horizontally andinclined as disclosed by United States Patent Application PublicationNo. U.S. 2011/0247367 of Nitschke et al. entitled Press Bending StationAnd Method For Bending Heated Glass Sheets, the entire disclosure ofwhich is hereby incorporated by reference.

As illustrated in FIG. 3, a lower press ring support frame 50 of thepress forming apparatus 36 supports a lower press ring 52 that has anupwardly concave shape and is received within the wheel bed 34 below thewheels 44 of the wheel conveyor assemblies 40 in a ring shape thereofwhere no wheel assemblies are located. The construction of the lowerpress ring is hereinafter more fully described. As illustrated in FIG.3, an upper mount 56 of the press station 12 supports an upper pressmold 58 of the press forming apparatus 36. This upper press mold 58 hasa downwardly facing convex forming face 60 complementary to the upwardlyconcave shape 54 of the lower press ring 52.

An actuator collectively indicated by 62 in FIG. 3 is configured toprovide operation of the system as is hereinafter described. Theactuator 62 initially provides relative vertical movement between thelower press ring 52 and the wheel bed 34 and between the lower pressring and the upper press mold 58 to move the heated glass sheet abovethe wheel bed and ultimately into pressing engagement between the lowerpress ring and the upper press mold to press form the glass sheet as ishereinafter more fully described. As disclosed, the actuator not onlymoves the lower press ring 52 upwardly but also moves the upper pressmold 58 downwardly so as to more rapidly decrease the spacing betweenthe lower press ring and the upper mold and thereby reduces the cycletime. However, it is possible to only move the lower press ring 52upwardly to perform the pressing operation but with a longer cycle time.

The press station 12 as illustrated by FIG. 3 and described above hasthe wheel bed 34 provided with an upwardly curved shape in a directiontransverse to the direction of conveyance along which the wheel bedreceives the heated glass sheet corresponding to the initially formedshape provided by the roll forming station 16 illustrated in FIGS. 1 and2. More specifically, the lower base structure 38 of the wheel bed 34includes a plurality of rails 64 that extend along the direction ofconveyance and have different elevations, as provided by schematicallyindicated adjusters 65 as shown in FIG. 3, along a direction transverseto the direction of conveyance to provide the curved shape of the wheelbed.

With reference to FIGS. 5 and 6, the upper press mold 58 has its formingface 60 provided with an array of holes 61 at which a vacuum is providedfrom a vacuum source 66 shown in FIG. 1 so as to support the formedglass sheet after the press forming and ensure forming of the glasssheet to the shape of the forming face. Upon downward movement of thelower press ring 52 and upward movement of the upper press mold 58provided by actuator 62, a shuttle 68 of the final processing station 18is moved by an actuator 70 to move a delivery ring 72 toward the leftbelow the upper mold 58. Termination of the vacuum provided by thevacuum source 66 may then be accompanied by the supply of pressurizedgas to the upper mold surface 60 to release the glass sheet onto thedelivery ring 72 and the shuttle actuator 70 then moves the shuttle 68back toward the right to the position illustrated such that the deliveryring 72 and the formed glass sheet thereon are delivered for finalprocessing such as slow cooling for annealing or more rapid cooling byair quenching for heat strengthening or tempering.

With continuing reference to FIG. 3, the actuator 62 previouslydescribed includes a lower vertical operator 74 for moving the lowerpress ring support 50 and the lower press ring 52 vertically relative tothe conveyor wheels 44 and also includes an upper vertical operator 76for moving the upper press mold 58 vertically relative to framework ofthe press station and relative to the lower press ring.

With reference to FIGS. 5 and 6, the upper mold 58 is supported on amold support 78 with its surface 60 facing downwardly during use with adownwardly convex shape as shown in FIG. 5. This downwardly facing moldsurface 60 has curvature in transverse directions as illustrated in FIG.6 by the phantom line C that is curved along the direction of conveyanceand by the phantom line T that is curved along a direction transverse tothe direction of conveyance.

As illustrated in FIGS. 7 and 8, the lower press ring 52 includes a pairof rigid upwardly concave end portions 80 that are spaced laterally fromeach other relative to the direction of conveyance and that have rigidupwardly concave curved shapes along the direction of conveyance.Actually due to their somewhat converging shape as illustrated best inFIG. 8, the lower press ring end portions 80 converge slightly along thedirection of conveyance and thus also extend to some extent transverselyto the direction of conveyance C. The lower press ring 52 also includesa pair of rigid upwardly concave intermediate portions 82 spaced fromeach other along the direction of conveyance with rigid upwardly concavecurved shapes extending transversely to the direction of conveyancebetween the end portions 80 of the lower press ring. As is hereinaftermore fully described, the end portions 80 and the intermediate portions82 of the lower press ring 52 are mounted on the lower support 50 so asto be movable vertically together with each other and independently ofeach other. More specifically, cylinders 84 respectively associated withthe lower press ring end portions 80 are connected to the press ringactuator 62 and operated to provide vertical upward movement of thepress ring end portions during the press forming operation as describedbelow. This upward movement of the lower press ring end portions 80relative to the intermediate portions 82 is illustrated in FIGS. 9 and10.

With reference to FIG. 11, the press forming cycle begins as theinitially formed glass sheet is conveyed on the wheel bed 34 into thepress station 12 above the lower ring 52 and below the upper mold 58with its downwardly facing surface 60 which has convex curvature bothalong and transverse to the direction of conveyance in complementaryrelationship to the end portions 80 and intermediate portions 82 of thelower press ring 52. The initially formed glass sheet G then has upperend portions 86 with straight line elements and an intermediate portion88 that also has straight line elements as previously discussed.

After the initially formed glass sheet is received within the pressstation as shown in FIG. 11, the processing proceeds as the lower pressring 52 is moved upwardly by the press system actuator as previouslydescribed to lift the glass sheet upwardly off of the conveyor wheel bed34 as shown in FIG. 12. The end portions 80 of the lower press ring 52are then moved upwardly relative to the intermediate portions 82 of thelower press ring to press the end portions 86 of the glass sheet Gagainst the downwardly facing surface 60 of the upper mold 58 as shownin FIG. 13. This upward movement of the lower press ring end portions 80proceeds without an accompanying movement of the intermediate portions82 of the lower press ring so that the ring end portions move upwardlyrelative to the intermediate portions. More specifically, theintermediate portions 82 of the lower press ring 52 do not move upwardlyas fast as its end portions 80 during the upward movement of the endportions 80 whose pressing of the glass sheet end portions 86 againstthe mold surface 60 provides curvature to their straight line elementsalong the direction of conveyance. The intermediate portion 88 of theglass sheet G which has not yet contacted the mold surface 60 still hasits straight line elements at this stage of the press cycle. It is alsopossible for the intermediate portions 82 of the lower press ring 52 toremain stationary during the continued upward movement of the endportions 80, however this results in a longer cycle time.

The press ring actuator moves the intermediate portions 82 of the lowerpress ring 52 upwardly relative to the press ring end portions 80 topress the intermediate portion 88 of the glass sheet G against thecurved mold surface to provide curvature to its straight line elementsalong the direction of conveyance. Thus, the entire glass sheet then hascurvature along transverse directions.

When glass sheets are formed with curvature in transverse directions,the periphery of the glass sheet is too long to provide the formingwithout extra glass being present, and this extra glass is greatest atthe locations farthest from the glass center, i.e., at the end portions86. By forming the glass sheet end portions 86 with the transversecurvature initially, the excess peripheral glass is reduced at theselocations and shared with the edges of the intermediate portion.

The press forming of this application has particular utility withvehicle windshields where the end portions of the glass sheet aremounted on the front windshield pillars at locations where anydistortion causes greater optical problems than at the upper roof edgeof the windshield and the lower cowl edge that extend along the oppositeextremities of the glass sheet intermediate portion 88.

It should be mentioned that the spacing between the intermediate portion88 of the glass sheet and the mold surface 60 as shown in FIG. 13 isexaggerated for purposes of illustration. More specifically, for aconventional size vehicle windshield glass sheet, this spacing is onlynominally about 3 centimeters (slightly more than an inch). Furthermore,the processing can proceed even if the intermediate portion 88 of theglass sheet contacts the upper mold surface 60 while the glass sheet endportions are being pressed against the upper mold surface so long asthere is no significant curvature provided to the straight line elementsof the glass sheet intermediate portion until after the glass sheet endportions have been pressed against the upper mold surface to provide thecurvature to their straight line elements. The term “no significantcurvature” as used herein means the maximum “depth of curvature” fromthe glass sheet to a straight line between its extremities to which itsstraight line elements extend is no greater than 20% and preferably lessthan 10% of the maximum “depth of curvature” after the intermediateportion of the glass sheet has been fully formed.

With reference to FIGS. 7-10, the intermediate portions 82 of the lowerpress ring 52 are mounted on the support frame 50 by adjusters 90 which,as disclosed, are threaded adjusters whose rotational adjustment raisesand lowers the adjacent portion of the intermediate portion to providethe required shape. A pair of connections generally indicated by 92mount the end portions 80 of the lower press ring on the support frame50 for vertical movement with respect thereto and with respect to theintermediate portions 82 of the lower press ring. The connections 92 asdisclosed include pivotal arms 94 having first ends 96 pivotally mountedon the support frame 50 and second ends 98 that respectively mount thepress ring end portions 80 at their opposite extremities.

As best shown in FIG. 7, the lower press ring end portions includeoperators 100 which each have a rotatable shaft 102 mounted for rotationon the support frame 50 by an associated pair of bearings 104. Adjacentone end of the shaft 102, a lever arm 106 has a pivotal connection 108to the piston connecting rod of the cylinder 84 whose operation providesthe independent movement of the lower press ring end portions 80. Theforming station actuator 62 in addition to operating the lower pressring operator 74 and the upper press mold operator 76, also operates thecylinders 84.

Each end of each shaft 102 also includes a lever arm 110 which, as bestshown in FIGS. 9 and 10, is pivotally connected to one end of anadjuster 112 whose other end is connected to an extension 114 of theadjacent second end of the pivotal arm 94 of the associated ring endportion connection 92. Threaded adjustment of the adjusters 112 providesvertical adjusting movement of the associated pressed ring end portion80 relative to the press ring intermediate portions 82. Since the leverarm 106 of each operator 100 is on the opposite side of the associatedshaft 102, downward movement of the piston connecting rod of cylinder 84provides upward movement of the associated pressed ring end portion 80relative to the press ring intermediate portions 82. After the pressring end portions 80 have provided the curvature to the straight lineelements of the glass sheet end portions 86 as previously described inconnection with FIG. 13, the fluid pressure suppled to the cylinders 84can be reduced to facilitate movement of the glass sheet end portionsalong the mold surface as the intermediate portion is moved upwardly asshown in FIG. 14 to complete the forming. The amount of this movement toaccommodate the difference in the chordal lengths of the glass sheetbetween FIGS. 13 and 14 is relatively small and operation to date hasshown that satisfactory forming can be performed without the pressurereduction even though it may be helpful for some shapes.

While exemplary embodiments are described above, it is not intended thatthese embodiments describe all possible forms of the invention. Rather,the words used in the specification are words of description rather thanlimitation, and it is understood that various changes may be madewithout departing from the spirit and scope of the invention.Additionally, the features of various implementing embodiments may becombined to form further embodiments of the invention.

What is claimed is:
 1. A glass sheet press station comprising: aconveyor for conveying along a direction of conveyance a heated andinitially formed glass sheet having an upwardly concave shape includingupper end portions spaced laterally from each other with respect to thedirection of conveyance and a lower intermediate portion that extendstransversely with respect to the direction of conveyance between the endportions, with the upper end portions and the lower intermediate portionhaving straight line elements, and with the glass sheet curvedtransversely to the straight line elements; a lower ring over which theglass sheet is conveyed, the lower ring including a support frame andalso including a pair of rigid upwardly concave end portions on thesupport frame spaced laterally from each other relative to the directionof conveyance with rigid upwardly concave curved shapes along thedirection of conveyance, the lower ring further including a pair ofrigid upwardly concave intermediate portions on the support frame spacedfrom each other along the direction of conveyance with rigid upwardlyconcave curved shapes extending transversely to the direction ofconveyance between the end portions of the lower ring, the end portionsof the lower ring each including a connection that permits verticalmovement thereof relative to the support frame, and the intermediateportions of the lower ring each including a connection that preventsmovement thereof relative to the support frame so the end portions andthe intermediate portions are movable vertically together with eachother and independently of each other; an upper mold located above thelower ring and having a downwardly facing surface with downwardly convexcurvature both along and transverse to the direction of conveyance incomplementary relationship to the curvature of the end portions andintermediate portions of the lower ring; and an actuator configured to:initially move the end portions and the intermediate portions of thelower ring upwardly together with each other by upward movement of thesupport frame to lift the initially formed glass sheet upwardly off ofthe conveyor; then move the end portions of the lower ring upwardlyrelative to the support frame and the intermediate portions of the lowerring to move the end portions of the glass sheet upwardly into contactwith the downwardly facing surface of the upper mold to providecurvature to the straight line elements of the end portions of the glasssheet while the intermediate portion of the glass sheet has not yet beenformed by the upper mold; and thereafter move the support frame upwardlyto move the intermediate portions of the lower ring upwardly relative toits end portions to contact the intermediate portion of the glass sheetwith the downwardly facing surface of the upper mold to providecurvature to the straight line elements of the intermediate portion ofthe glass sheet so the entire glass sheet has curvature in transversedirections.
 2. A glass sheet press station as in claim 1 wherein thelower ring includes a pair of pivotal connections that respectivelypivotally mount the end portions of the lower ring on the support framefor the vertical movement with respect thereto and with respect to theintermediate portions of the lower ring.
 3. A glass sheet press stationas in claim 2 wherein the pair of pivotal connections each includespivotal arms having first ends that are pivotally mounted on the supportframe and second ends that respectively mount the associated end portionof the lower ring.
 4. A glass sheet press station as in claim 1 whereinthe actuator includes cylinders for applying upward force to the endportions of the lower ring so as to move the lower ring end portionsupwardly relative to the support frame and the intermediate portions toprovide the movement of the end portions of the glass sheet upwardlyinto contact with the downwardly facing surface of the upper mold toprovide forming thereof along the direction of conveyance while theintermediate portion of the glass sheet has not yet been formed by theupper mold.
 5. A glass sheet press station as in claim 4 wherein theactuator operates the cylinders to reduce the upward force applied tothe end portions of the lower ring as the intermediate portions of thelower ring are moved upwardly relative to the end portions of the lowerring to facilitate movement of the glass sheet end portions relative tothe downwardly facing surface of the upper mold as the intermediateportions of the lower ring move the intermediate portion of the glasssheet into contact with the downwardly facing surface of the upper moldto provide the forming thereof along the direction of conveyance.
 6. Aglass sheet press station as in claim 1 wherein the lower ring includesadjustors for adjusting the positions of its rigid upwardly concave endportions and its rigid upwardly concave intermediate portions relativeto the support frame and each other.
 7. A glass sheet press formingsystem comprising: a conveyor for conveying glass sheets along adirection of conveyance; a furnace including a heating chamber throughwhich the conveyor conveys glass sheets from an entrance end of thefurnace toward an exit end thereof for heating in preparation forforming; the furnace adjacent its exit end including inclined rolls ofprogressively increasing inclination along the direction of conveyanceso as to initially form each glass sheet with an upwardly concave curvedshape extending transversely with respect to the direction of conveyancewith upper end portions and a lower intermediate portion extendingbetween the end portions, with the upper end portions and the lowerintermediate portion having straight line elements, and with the glasssheet curved transversely to the straight line elements; a press stationto which the conveyor conveys the initial formed glass sheet at alocation downstream from the exit end of the furnace, the press stationincluding a lower ring over which the glass sheet is conveyed, the lowerring including a support frame and also including a pair of rigidupwardly concave end portions on the support frame spaced laterally fromeach other relative to the direction of conveyance with rigid upwardlyconcave curved shapes along the direction of conveyance, the lower ringfurther including a pair of rigid upwardly concave intermediate portionson the support frame spaced from each other along the direction ofconveyance with rigid upwardly concave curved shapes extendingtransversely to the direction of conveyance between the end portions ofthe lower ring, the end portions of the lower ring each including aconnection that permits vertical movement thereof relative to thesupport frame, and the intermediate portions of the lower ring eachincluding a connection that prevents movement thereof relative to thesupport frame so the end portions and the intermediate portions aremovable vertically together with each other and independently of eachother; the press station also including an upper mold located above thelower ring and having a downwardly facing surface with convex curvatureboth along and transverse to the direction of conveyance incomplementary relationship to the curvature of the end portions andintermediate portions of the lower ring; and an actuator configured to:initially move the end portions and the intermediate portions of thelower ring upwardly together with each other by upward movement of thesupport frame to lift the initially formed glass sheet upwardly off ofthe conveyor; then move the end portions of the lower ring upwardlyrelative to the support frame and the intermediate portions of the lowerring to move the end portions of the glass sheet upwardly into contactwith the downwardly facing surface of the upper mold to providecurvature to the straight line elements of the end portions of the glasssheet while the intermediate portion of the glass sheet is still belowand has not yet been formed by the upper mold; and thereafter move thesupport frame upwardly to move the intermediate portions of the lowerring upwardly relative to its end portions to contact the intermediateportion of the glass sheet with the downwardly facing surface of theupper mold to provide curvature to the straight line elements of theintermediate portion of the glass sheet so the entire glass sheet hascurvature in transverse directions.